[SR-9129] move installed libraries to architecture subdirectory

[compnerd]

Previous ID	SR-9129
Radar	None
Original Reporter	@compnerd
Type	Task

Additional Detail from JIRA

Votes	0
Component/s	Compiler, Project Infrastructure, Standard Library
Labels	Task, Android, Linux, StarterBug, build
Assignee	None
Priority	Medium

md5: 9e1d4d406e122aeeb675d43067a2fdc4

Issue Description:

The current installation of the libraries in usr/lib/swift/<os> does not work for non-MachO targets. We need to move the libraries to usr/lib/swift/<os>/<arch> for ELF and PE/COFF targets.

[belkadan]

I thought we landed this already? There was definitely a PR working on it.

[compnerd]

No, it isn't merged, there is still a few more patches left for that. Daniel Rodriguez was working on this.

[compnerd]

Removing this from the Windows set as the Windows support for this is more or less complete. In fact, we may wish to move back towards unarchitectured directories for the swift modules as they are multi-architecture friendly now.

[finagolfin]

@compnerd, I implemented this in #63782 and associated pulls, but this approach was rejected in favor of using triple-named module directories instead, so you can close this issue now.

My recently-opened #63645 tracks the overarching issue of doing something about these Swift runtime libraries.

[finagolfin]

Closing in favor of #63645, where I've tried to restart discussion on what to do about this long-standing issue.